package cn.doourbest.learnspring.tomcat;

import java.util.*;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.function.Predicate;

/**
 * @description:
 * @author: zhangsc
 * @create: 2019/11/6
 */
public class MainOptional {

    public static void main(String[] args) {

        Map<String,Long> map = new HashMap<>();

        AtomicBoolean atomicBoolean = new AtomicBoolean(true);
        System.out.println(atomicBoolean.compareAndSet(false, true));
    }

}
